The invention relates to a hydrostatic machine having a control device for adjusting the displacement volume of the hydrostatic machine, wherein the control device comprises a return element for controlling a regulating valve.
When adjusting displacement volumes of hydrostatic machines, e.g., axial piston machines, maximum and minimum displacement volumes can generally be adjusted by way of integrated control devices. These maximum and minimum displacement volumes are fixed within an axial piston machine by mechanical stops. The control of minimum or maximum volumes is thus associated with a control of minimum and/or maximum stop regions. The stressed stop regions have a considerable load placed thereon in the case of extremely quick pivoting actions which extend to the stressed mechanical stop regions. These loads result in signs of wear and material fatigue in the components of the control systems located in the flow of force.
The loading of the components of the mechanical limitation located in the flow of force could cause the components to become worn or to change such that the operation and thus quality of operation of the control devices—whose component parts also include the minimum or maximum stop regions—becomes impaired. For example, wear on a mechanical stop changes the displacement volume, wherein the movement of an adjusting mechanism is limited by the stop. A control pressure acting in the control device is adjusted by a regulating valve in dependence upon the position of the control device.
It is thus the object of the invention to provide a hydrostatic machine in which the hard stopping of components on the mechanical maximum and/or minimum stop regions is prevented and which thus comprises a displacement volume limitation which is not subject to wear.